“Salt is born of the purest of parents: the sun and the sea.”—Pythagoras (580 BC-500 BC)

We’re all familiar with the tiny, white crystals in the saltshaker. But while salt has been used to season and preserve food since prehistory, refined salt was unknown until Morton’s addition of anti-caking agents to sodium chloride in 1910. Modern processing methods have made what was once a scarce, expensive commodity into the world’s main food seasoning. Using very high temperatures to dry seawater, processing removes impurities and natural companion minerals found in sea salt, creating 99.7% pure sodium chloride. It also adds iodine; the sugar dextrose to stabilize the iodine; and anti-caking agents like aluminum silicate, magnesium carbonate or calcium silicate to absorb moisture and keep the salt dry in humid conditions.

Line in the Salt

Today, many believe that highly processed sodium chloride is not a wise health choice. Shannon Hayes, author of The Grassfed Gourmet Cookbook (Ten Speed Press), is concerned that in order to keep the salt dry and white, refiners add bleaching agents and aluminum compounds, which have been linked to Alzheimer”s.

“The processing strips salt from nutrients such as magnesium salts—which I have found essential to my own well-being. I feel good, clean salt is critical to healthy brain function,” she says.

Like Hayes, many prefer natural sea salts for their lower sodium and higher mineral content. According to the Salt Institute, seawater contains about 3.5% (by weight) dissolved minerals, including calcium, magnesium, potassium, iron, sulfur and 80 other trace elements. This means natural sea salts are slightly lower in sodium (97-98% sodium chloride). Many of these minerals are abundant in other dietary sources (calcium in dairy and magnesium in green vegetables, for example). And sea salt has only minute amounts of iodine, which is necessary for normal thyroid function; deficiency is linked to goiter and some forms of mental retardation. According to the Mayo Clinic website, “Sea salt and table salt have the same nutritional value. The differences are in taste and texture.”

Others are turning to unprocessed sea salts for their variety of flavors and textures. Fleur de sel from the coast of Brittany is favored by French chefs. Vogue food writer Jeffrey Steingarten prefers English Maldon’s crunchy, pyramid-shaped flakes. Pierre Laszlo, author of Salt: Grain of Life (Harper Perennial), compares salt to wine: “Wine is an aqueous solution of ethanol and yet different wines taste differently and some are definitely better. Why? Because of the trace amounts of hundreds of different molecular species. Salt is no different. Its taste and its health benefits stem from trace impurities. To me, the (impure) grey salt from Guerande has a richer flavor than the (very pure) flower of salt, also from Guerande.”

The unique characteristics of regional salts like Himalayan rock salt, Hawaiian Kilauea black sea salt or Utah’s Jurassic come from their place of origin. Mark Bitterman, who with his wife Jennifer sells more than 50 different salts at The Meadow in Portland, Oregon, explains the complexity of unrefined sea salt: “Every crystal combines unique qualities of mineral content, moisture, size, shape and color that affect the flavor and texture of food in various ways.” Bitterman cautions that all sea salts are not equal. “Solar-evaporated artisan sea salts come from pristine waters and require more craftsmanship, care and time in production than do industrially manufactured sea salts,” he explains. According to Bitterman, most salt in the U.S. comes from the polluted waters of the Caribbean Sea. Since both the minerals and impurities are removed in processing, this is not a major concern.

Seasoning salts—smoked salts and blends of salt with spices—also add flavor. Most people are familiar with garlic or celery salt, but today’s exotic flavor blends include Turkish black pyramid sea salt, which gets its color and flavor from charcoal, and Tea-smoked sea salt, which combines Mediter-ranean spices with flaky salt. Didi Davis of Massachusetts-based Salt Traders, which sells many rare sea and herbed salts, says, “A natural product, gourmet salts have gained popularity over the last decade. The trend has spread from restaurant chefs to home cooks.”

Some chefs, however, feel the texture and color of gourmet salt is lost while cooking, and that it is best saved for a finishing touch where the unique crunch and color of various salt crystals is more noticeable. When salt is dissolved, they prefer the clean flavor, crystal texture and cheaper price of kosher salt. While this coarse salt is refined, it is pure sodium chloride without additives. At a dollar or more an ounce for gourmet salts (versus just pennies for an ounce of kosher or table salt) each cook must decide if gourmet salt is worth the price.